diff --git a/contents/5.2.1.1-basic-concepts-to-review.md b/contents/5.2.1.1-basic-concepts-to-review.md index 75ebe0a3..42050455 100644 --- a/contents/5.2.1.1-basic-concepts-to-review.md +++ b/contents/5.2.1.1-basic-concepts-to-review.md @@ -114,7 +114,7 @@ Beta is my favorite distribution (what do you mean you don't have a favorite dis Say, we have a coin with an unknown probability of turning heads. Let $$p$$ represent this probability. After $$n + m$$ flips, we get $$n$$ heads and $$m$$ tails. We might want to estimate that $$p = \frac{n}{n+m}$$. However, this is unreliable, especially if $$n+m$$ is small. We'd like to say something like this: $$p$$ can also be more than, less than, or equal to $$\frac{n}{n+m}$$, the values further away from $$\frac{n}{n+m}$$ having a smaller probability. And the higher the value of $$n+m$$, the higher the probability of $$p$$ being $$\frac{n}{n+m}$$. The beta distribution allows you to do that. -The beta random variable is represented using two variables: $$\alpha$$ to represent the number of successes and $$\beta$$ to represent the number of failures. The beta distribution can represent beyond coin flips. In fact, $$\alpha$$ and $$\beta$$ can rerepsent continuous value (though they can't be non-positive). +The beta random variable is represented using two parameters: $$\alpha$$ to represent the number of successes and $$\beta$$ to represent the number of failures. The beta distribution can represent beyond coin flips. In fact, $$\alpha$$ and $$\beta$$ can rerepsent continuous value (though they can't be non-positive). $$ x \sim \text{Beta}(\alpha, \beta) \text{ with } 0 < \alpha, \beta \\ @@ -175,4 +175,4 @@ $$ A conditional probability distribution gives the probability of a subset of events occurring assuming that other events also occur. One example is $$P(X|Y)$$. --- -*This book was created by [Chip Huyen](https://huyenchip.com) with the help of wonderful friends. For feedback, errata, and suggestions, the author can be reached [here](https://huyenchip.com/communication/). Copyright ©2021 Chip Huyen.* \ No newline at end of file +*This book was created by [Chip Huyen](https://huyenchip.com) with the help of wonderful friends. For feedback, errata, and suggestions, the author can be reached [here](https://huyenchip.com/communication/). Copyright ©2021 Chip Huyen.*